There are an estimated 2.5 million people in the US who are speech impaired to the extent that it is considered a functional limitation. Today, many of these people lack the ability to communicate effectively with others around them. In a previous project, we designed a portable electronic device called Pacer. Pacer has the unique patent-pending feature of incorporating two graphical touch-sensitive displays: one for the AAC user and the other for the interlocutor (communication partner). In this project, we aim to build on this previous research by designing communication software the takes full advantage of the dual-display feature. A dual-display AAC device holds tremendous promise. It can improve understandability and retention of messages communicated by AAC users. It can facilitate face-to-face communication and encourage greater social interaction for the AAC user. The ability to output graphics on the interlocutor display opens the possibility to more effective communication through pictures. For example, when asked "how are you?", an AAC user could output the message "Great?", while simultaneously displaying a video of someone jumping up and clicking their heels. This level of emotional response is simply not possible with today's device. This research will investigate the efficacy of using the two displays for communication. Pacer has a number of other hardware features that we also seek to take advantage of. It is a hardware platform for which little software currently exists - a framework which now needs to be fleshed out. That is the purpose of this research project: to investigate how to best take advantage of the Pacer hardware and then write software to implement those features.